peggy
esprima
Our great sponsors
peggy | esprima | |
---|---|---|
8 | 8 | |
806 | 6,962 | |
7.7% | 0.4% | |
8.9 | 0.0 | |
25 days ago | about 1 year ago | |
JavaScript | TypeScript | |
MIT License | BSD 2-clause "Simplified" License |
Stars - the number of stars that a project has on GitHub. Growth - month over month growth in stars.
Activity is a relative number indicating how actively a project is being developed. Recent commits have higher weight than older ones.
For example, an activity of 9.0 indicates that a project is amongst the top 10% of the most actively developed projects that we are tracking.
peggy
- Peggy: Parser Generator for JavaScript
- GitHub - peggyjs/peggy: Peggy: Parser generator for JavaScript
- Peggy: Maintained fork of PEG.js parser generator
-
Creating a custom parser with PEGJS
The PEG.js project got taken over by a new maintainer who locked everyone else out, never shipped a release, and then ignored repeated requests to transfer the project back to the community. So the community forked it to a new project - Peggy, which is where ongoing development happens: https://github.com/peggyjs/peggy
-
How to make your own programming language in JavaScript
NOTE: The original PEG.js project is not maintained anymore, but there is a new fork, Peggy that is maintained and it's backward compatible with PEG.js so it will be easy to switch.
-
Show HN: DTL: a language and JavaScript lib to transform and manipulate data
Thanks. Yes, DTL's core textual syntax is described with PEG. I make use of the Peggy (https://peggyjs.org/) PEG processor to build up the AST that is used to actually process DTL.
There are C based PEG processors, which I've looked at once or twice also, but I haven't sat down to try to convert it. Mostly out of a desire to get the existing module to work well. A working module for one language is better than a partially working module for multiple. :P
-
Parsing in JavaScript: all the tools and libraries you can use
hmm this article is a bit outdated; peg.js (mentioned in the article) has been discountined for a few years now; recently the project was picked up by another team under the name peggy.js https://github.com/peggyjs/peggy
esprima
-
ESLint: under the hood
Focusing again on ESLint, the parser used by the linter is called Espree. This is an in-house parser built by the ESLint folks to fully support ECMAScript 6 and JSX on top of the already existing Esprima. The Espree module provide APIs for both tokenization and parsing that you can easily test out.
-
Why you don’t need TypeScript
For TypeScript we have used AST transforms from their compiler API, and for plain JavaScript we did a similar thing using ESPrima. This helped us implement some simple optimizations like stream fusion (combining .filter and .map into a single operation) or avoiding extra object allocations in vector math, which led to nice performance improvements in code that does heavy computation (we process large amounts of data on the server and store results of physics simulations).
-
Algorithm to simplify a 100-variable Boolean expression?
I used ESPrima, but any parser would do in this case. I then wrote a simple function to extract all "atomic" non-boolean expressions from it.
-
How to make your own programming language in JavaScript
AST is an acronym for Abstract Syntax Tree. It's the way to represent code in a format that tools can understand. Usually in form of tree data structure. We will use AST in the format of an Esprima, which is a JavaScript parser that outputs AST.
-
What the heck is an Abstract Syntax Tree (AST) ?
esprima
-
Abstract Syntax Trees: They're Actually Used Everywhere -- But What Are They?
Create an AST: Esprima
-
We Switched from Webpack to Vite
The thread was originally about CRA vs Vite size on disk (or implicitly, if we're applying it to real world applications, network cost in CI job startup times). And like I said, surrogate pairs don't apply to ASCII.
See this[0] for reference. Note how the first byte must fall within a certain range in order to signal being a surrogate pair. This fact is taken advantage of by JS parsers to make parsing of ASCII code faster by special casing that range, since checking for a valid character in the entire unicode range is quite a bit more expensive[1].
[0] https://github.com/jquery/esprima/blob/0911ad869928fd218371b...
[1] https://github.com/jquery/esprima/blob/0911ad869928fd218371b...
-
How to create your own language that compile to JavaScript
If you want to learn more about parsing, reading the code of an actual recursive parser might be a better idea. Esprima is a decent place to start if you're interested in JS grammar. Then you can look at the babel handbook to learn more about AST transformations. From there, the literature gets quite a bit more heavy. If you get this far and are willing to push further, you'll probably want to grab yourself a copy of the dragon book at a minimum.
What are some alternatives?
PEG.js - PEG.js: Parser generator for JavaScript
estree - The ESTree Spec
lezer - Dev utils and issues for the Lezer core packages
estraverse - ECMAScript JS AST traversal functions
ohm - A library and language for building parsers, interpreters, compilers, etc.
esbuild-loader - Webpack loader for esbuild: Speed up your build ⚡️
purescript - A strongly-typed language that compiles to JavaScript
babel-handbook - :blue_book: A guided handbook on how to use Babel and how to create plugins for Babel.
lens-toml-parser - Lenses for toml-parser
escodegen - ECMAScript code generator
jquery.terminal - jQuery Terminal Emulator - JavaScript library for creating web-based terminals with custom commands
vite-plugin-vue2 - Vue2 plugin for Vite